How to use php functions in smarty

Output results: 16 2

Test: -=-=-=-=this is four

Instructions: Use four variables to handle 1, 2, 3, and 4 unavailable parameters respectively. Here is a record. When calling variables in the template, when there is only one parameter, just {$str1|function name}. When there are two functions When there are three parameters, {first parameter | function name: second parameter}, when there are three parameters, {first parameter | function name: second parameter: third parameter}, when there are 4, 5,,,parameters, and so on,,,,,,,,,,,,

When programming, I used this:

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